Cartridge feeding mechanism



Aug. 18, 1959 R. H. COLBY 2,899,865

CARTRIDGE FEEDING MECHANISM Filed June 27, 1956 3 Sheets-Sheet 1 I 3311111. 58 5e 60 7 66 25 In M A /V X I l INVENTOR.

Richard H. Bulky BY MZ-JMQMQLQ-MQJ' Aug. 18, 1959 R. COLBY 2,899,855

7 CARTRIDGE FEEDING MECHANISM Filed June '27, 1956 3 Sheets-Sheet 2 IN VEN TOR.

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Ri EhuIEL Hllulhy I Aug. 18, 1959 R. H. COLBY 2,899,865

CARTRIDGE FEEDING MECHANISM Filed June 27, 1956 3 Sheets-Sheet 5 Fig-'5-25 36 C if ' .INVEN TOR.

E i EhurflHLnEy CARTRIDGE FEEDING MECHANISM Richard H. Colby, SouthHadley, Mass, assignor to the United States of America as represented bythe Sec- 3, retary of the Army Application June 27, 1956, Serial No.594,334

1 Claim. (21. 89-33) (Granted under Title as, US. Code 1952 see. 266)The invention described herein may be manufactured and used by or forthe Government for governmental purposes without the payment of anyroyalty thereon.

' My invention relates to a recoil operated automatic gun and moreparticularly to a cartridge feeder therefor.

A conventional recoil operated gun is provided with a barrel which isdisposed for reciprocation responsive to the discharge of a cartridgetherein and a feed device having pawls therein for engaging anammunition belt to propel the links thereof equal distances to astripping position therefor respectively responsive to the recoil andcounterrecoil operation of the barrel. greater energy which is in thebarrel during the recoil stroke thereof, the period of the recoilportion of the ;operating cycle is substantially half the counterrecoilperiod, resulting in a wide differential in maximum stresses created inthe ammunition belt responsive to the pawl operation. Further, astationary stop is provided .in the feed device for engagement with thecases of car- :tridgesto determine the stripping position thereof.

An object of my invention, therefore, is to provide a i'cartridge feeddevice for producing substantially equal' stresses on the links of anammunition belt responsive to the recoil and counterrecoil operation ofthe feeder.

Another object of my invention is to provide such a feed device operatedby a pivoted lever with arms of varied lengths.

A further object of my invention is to provide such ..'a device having amovable stop for engaging the belt links to determine the strippingposition of the cartridges.

In carrying out my invention, the recoil and counterrecoil pawls arepivoted and spring-biased on laterally slidable carriages disposedforopposite reciprocation and .operated by means of a lever in the receiverdisposed for a pivotal operation responsive to recoil and counterrecoilof the barrel. j The carriages are joined to the lever at ;'distancesfrom the pivotal center thereof which are in direct ratio with therecoil and counterrecoil periods, to

. substantially equalize the maximum stresses produced in the ammunitionbelt responsive to operation of the pawls.

A pivoted stop is disposed on the carriage supporting the recoil pawlfor cooperation with the counterrecoil pawl to engage the lead link ofthe ammunition belt in the stripping position therefor.

For better understanding of my invention, reference directed to thefollowing description and the accom 1 'panying'drawings in which:

Fig. 1 is an elevational, partially cross-sectioned view I of the.feeding portion of a gun incorporating my invention;"

Because of the United States Patent O a 2,899,865 Patented Aug? 195.9

Fig. 7 is a view along line 7--7 of Fig. 3 with lever 36 and connectorbar 62 disposed axially. 7

Accordingly, a gun 12 having a receiver 14 is provided with a barrel 16disposed therein for recoil and counterrecoil stroke operation. Thevelocity of barrel 16 during the recoil'stroke is approximately twicethat of the counterrecoil stroke because of the expenditure of therecoil forces during the course of the operating cycle and theabsorption of a part of the forces by the engagement of the barrel witha conventional buffer mechanism (not shown) at the end of the recoilstroke.

Gun 12 is suppliedwith cartridges 18 which are releasably engaged inlinks 20 to form a belt 22 and such belt is fed to the firearm by meansof a feeder 24 mounted I on receiver 14. Feeder 24 includes a tray 26for slidably supporting belt 22 during passage thereof from an feedthroat 19 is provided in tray 26 midway of the ports 21 and 23 to permittransfer of the cartridges 18 from feeder 24 into receiver 14 and thechamber of barrel 16. Mounted to the underside of top portion 25 so asto be spaced therefrom are a rear guide plate 27 and a front guide plate29. Rear guide plate 27 is provided with ways disposed laterally alongthe underside thereof to slidingly mount a carriage 28 and a carriage 30so that carriage 30 is disposed under carriage 28. Extending upwardlyfrom rear guide plate 27 is a cylindrical lug 42 upon which there ispivotally mounted a lever 36. A first pin depends from lever 36forwardly of lug 42 for extension through a clearance opening in frontguide plate 27 to be received by a hole 32 in carriage 28. Hole 32 issuitably elongated to compensate for the longitudinal displacementoffirst pin 35 therein as lever 36 is pivoted.

32. Second pin 39 is spaced from lug 42 twice the dist'ance whichseparates first pin 35 from such lug whereby,

' when lever 36 is pivoted, carriage 30 is moved twice the distance thatcarriage 28 is moved and, consequently, with twice the velocity.

Pivotally mounted to the end of carriage 28, which is adjacent entranceport 21, is a first pawl 44 which is spring biased for sequentialengagement with the links 20 for advancing belt 22 into feeder 24 whensuch carriage is moved awayfrom'such entrance port and such ,fir st pawlis rideable over the links when moved towards such port. Pivotallymounted to the opposite end of carriage 28 is a spring-biased stop 74which is extendable through an opening 31 in carriage 30 for engagementwith the front side of the link 20, which engages the cartridge 18disposed over feed throat 19, and thereby cooperates with a second pawl46 pivotally mounted to V the end of carriage 30 which is adjacententrance port 21 insecuring such link against lateral displacementduring extraction of, the cartridge therefrom as by a bolt I (notshown). A depressor 75 is spring-biased into resilient engagement withthe link 20 positioned over feed throat 19 to restrain such link againstvertical displacement.

' A cylindricalboss '64 extends upwardly from the top 60 mounted forsliding lateral movement along the underside of such front guide plate.Thus, movement of crosshead 60 is transferred by connector bar 62 tolever 36 for simultaneous and opposite movement of carriages 28 and 30.i

Crosshead 60 is actuated, responsive to reciprocation of barrel 16, by adevice including a longitudinally-disposed cylindrical member 50 whichis joined by a connector portion 51 to barrel 16 for reciprocationtherewith, a tubular member 48 which slidingly receives such cylindricalmember and is irnrnovably secured to receiver 14 by a bracket 49 and acollar 52 which is rotatably mounted on such tubular member. Extendingupwardly from collar 52 is an arm portion 53 which is terminated by acylindrical tip 56 rotatably received in a mating groove 58 provided incrosshead 60. A pin follower 54 is slidingly received in an axial bore57 in arm portion 53 and is biased by a spring 59 into slidingengagement with a cam groove 61 provided in cylindrical member 50whereby longitudinal reciprocation of such member with barrel 16 isconverted to pivotal movement of arm portion 53 which, in turn, isconverted to lateral reciprocation of crosshead 60.

The operation of feeder 24 is as follows:

When a cartridge 18 is discharged in barrel 16, the force of theexplosion recoils the barrel carrying with it cylindrical member 50which, through the sliding engagement of pin follower 54 with cam groove61, rotates collar 52 to pivot arm portion 53 and actuates crosshead 60.The sliding movement of crosshead 60 is translated to pivotal movementof lever 36 by the connection of connector bar 62 therewith and, throughsuch movement of the lever, carriages 28 and 30 are simultaneously movedin opposite directions. stroke of barrel 16, carriage 28 is actuated to,move the link 20 engaging the leading one of the cartridges in belt 22towards feed throat 19 through the engagement of first feed pawl 44 withsuch link. At the same time, stop 74 is simultaneously moved away fromfeed throat 19 and into engagement with side 76 of opening 31 to becammed thereby upwardly and away from engagement with belt 22, as shownin Fig. 6.

Upon the following counterrecoil stroke of barrel 16,

second pawl 46, which during the recoil stroke, was

moved over the leading cartridge, engages the link holding such leadingcartridge to complete the passage thereof to feed throat 19. As has beenexplained hereinbefore, the distance from lug 42 to pin 39 is twice thatbetween Thus, during the recoil such lug and pin 35 and thereby belt 22is moved one- 0nd pawl 46 into position over feed throat 19, stop 74 0is moved towards the feed throat from the opposite direction. Thereby,the link holding the leading cartridge is firmly secured over the feedthroat between stop 74 and second pawl 46 and beneath depressor 75, asbest shown by Fig. 5, when such cartridge is stripped from the engaginglink by such means as a bolt (not shown).

Because the distance between lug 42 and pin 39 is twice that betweensuch lug and pin 35, the velocity with which carriage 30 is moved istwice that of carriage 28 and as first pawl 44, mounted to carriage 28,engageably moves belt 22 during the recoil stroke of barrel 16 and assecond pawl 46, mounted to carriage 30, engageably 6 moves the beltduring the counterrecoil stroke of the barrel, compensation is made forthe differences in the velocity of the recoil and counterrecoil strokesof the '4 i I barrel so that a constant force is applied to theb'eltduring the operating cycle of the gun 12 to reduce undesirablestresses in the belt which cause breakages and other malfunctions.

Although a particular embodiment of the invention has been described indetail herein, it is evident that many variations may be devised withinthe spirit and scope thereof and the following claim is intended toinclude such variations.

I claim:

In combination with a firearm provided with a receiver, a barrel mountedfor reciprocation in the receiver in a recoil stroke and a counterrecoilstroke having a reduced velocity with a predetermined relationship tothat of the recoil stroke, and an ammunition belt composed of aplurality of linked cartridges, a feeder for engageably moving thecartridges in the ammunition belt into the firearm and having anentrance port and a feed throat, said feeder including a first carriageand a second carriage in superimposed relationship and slidinglydisposed for respective reciprocation between the entrance port and thefeed throat, a lever intermediately mounted between the front and rearends thereof on a vertically disposed lug for oscillating movement in aplane parallel to the path of movement of said first and secondcarriages, a crosshead slidingly disposed for reciprocation parallel tothe movement of said first and second carriages and forward thereof, cammeans for converting the longitudinal reciprocation of the barrel tolateral reciprocation of said crosshead, means for connecting saidcrosshead to the front end of said lever to move such end in thedirection from the entrance port to the feed second pin mounted to therear end of said lever at a distance from the lug which is related tothe distance of said first pin therefrom as the velocity of the recoilstroke of the barrel is related to the counterrecoil stroke thereofwhereby said first and second carriages are moved simultaneously inopposite directions and are moved with similar velocities duringmovement thereof away from the entrance port and towards the feedthroat, a first pawl pivotally mounted to said first carriage forengagement with the leadingcartridge in the ammunition belt during therecoil stroke of the barrel for unidirectionally moving the leadingcartridge from the entrance port towards the feed throat a portion ofthe distance therebetween, said portion having a relationship to theremaining distance to the feed throat as the velocity of thecounterrecoil stroke is related to that of the recoil stroke, and asecond pawl pivotally mounted to said second carriage for subsequentengagement with the leading cartridge to continue moving such cartridgeto the feed throat at a uniform velocity during the reducedvelocitycounterrecoil stroke of the barrel.

References Cited in the file of this patent UNITED STATES PATENTS709,883 Knight Sept. 30, 1902 2,223,004 Holek Nov. 26, 1940 2,644,365Maillard July 7, 1953 2,650,520 Lippert et al. Sept. 1, 1.953

FOREIGN PATENTS 897,534 France May 30, .1944

